High Hopes: Saving for High School with a Mobile Money Lock Box

This is an encouragement design in which we have two main treatment groups and a control. Parents of Standard 8 students in Kenyan primary schools attend meetings at which they are engaged in a discussion about saving for the transition to secondary school, which will occur in January 2015. All groups are given this information, and all parents are asked to estimate how much they would need to save in order to cover the costs of sending their child to high school. Our interventions include encouragement to use mobile phone based savings products, and exposure to text messages reminding parents of their savings goals.

2014-07-14

2015-01-31

Key outcomes are financial balances on mobile phone accounts, and other savings levels and accumulation of assets. In addition, we will document whether the children of study participants enter high school, which school they attend, and their test scores at the end of primary school.

We have two primary treatment groups and a control. The first main treatment group is encouraged to open a mobile phone based "lock savings account" from which balances cannot be withdrawn without penalty until January 2015. A second treatment group is encouraged to open a mobile phone based savings account that earns less interest but does not have any lock features. The control group receives no information about saving on their mobile phones.

In addition, we cross each group with a text message intervention that reminds parents of their specific savings goal, and how long they have left to achieve it.

Parents are interviewed in meetings held at 360 primary schools in three counties in Kenya. Randomization is at the school level stratified by county, using an office computer.

Randomization is at the school level.

Yes

360 primary schools.

Parents of 9,000 students

120 control, 120 mobile savings account, 120 mobile lock savings account

We assume a two level cluster randomized trial 2-CRT with level 1 being the student and level 2 being the class/teacher and level 3 being the school. The key parameters are the share of between school variance (rho_S). We have no prior data on which to draw this estimate so we assume conservative range of [0.05 0.2]. We assume that net recruitment at the school produces 20 parents who sign up for the savings products. We also assume that baseline data can explain about 30% of the variance of the outcome (we test for sensitivity to this assumption by showing the MDE-sample size locus when there are no covariates). Given the assumptions above and a total sample size of 120 schools per arm, we have 80% power to distinguish effect sizes as small as 0.105 (at the low end of the ICC) or 0.156 at the high end of the ICC.   Two possible scenarios: Firstly that uptake or compliance is considerably lower than the 20 student/families. We revise our cluster size assumptions to 10 students per cluster maintaining the baseline ICC and baseline covariate explanatory power assumptions. Our MDE now has the following range [0.132 0.171]. Secondly, if we assume an even more conservative scenario; no baseline covariates and an ICC of 0.4, then our MDE increases to 0.24.